The present invention relates generally to containers and more particularly to drawn and ironed containers.
The use of two-piece containers for packaging beer and/or carbonated beverages has become very popular in recent years. The two-piece container consists of a cylindrical container body that has a unitary end wall at one end thereof. A converted end having an opening mechanism is usually then double seamed to the open end of the container to produce a complete package.
In the formation of a drawn and ironed container, a flat circular disc is normally cut from a blank of stock material and is substantially simultaneously transformed into a shallow cup. This is done in a cupping machine or cupper in a can manufacturing plant.
The shallow cup is then transferred to a body maker, such as a drawing and ironing machine, wherein the shallow cup is initially reformed into a cup of different dimensions and substantially simultaneously passed through a plurality of ironing rings or dies which cooperate with a punch to decrease the wall thickness or the reformed cup and to transform the cup into a seamless container having a sidewall and an integral end wall. At the end of the stroke of the punch, the end wall is usually reformed to some configuration, such as an inwardly directed dome, to increase the pressure resistance of the container when the contents in the container are pressurized.
At the present time, most ends that are utilized for closing the open end of a drawn and ironed container incorporate the conventional type of removable tear strip as the opening means. In forming the finished end, a flat circular disc is reformed to have a flat central portion surrounded by a countersink at the periphery thereof and a peripheral flange or rim at the free end of the countersink which is adapted to be double seamed to the open end of the drawn and ironed container. This partially finished end is then converted to a complated end in a conversion press which normally has six stations with an integral rivet for connecting an opening tab being formed at the first and second station. At the third station, the end is scored to produce the removable section or tear strip while the tab is staked to the tear strip at the fourth and fifth stations. At the last station, the central panel is transformed to its final configuration, such as producing the desired stengthening beads as well as the indicia that is desired on the finished end.
With the recent emphasis on ecology, all can manufacturers are attempting to produce a container wherein the opening means remain with the container after the contents have been consumed. Examples of these types of ends include what is referred to as the "button" end in which one or two circular scores are produced in the end panel which is attached to the container body with a portion being unscored to define a permanent connection between the button and the remainder of the end. Another example of present attempts to produce an ecology end includes some type of permanent connection between the present day generally conventional tear strip and the remainder of the container. All of these attempts are directed towards producing an improved end which can be attached to a container body.